Guyver a.k.a Bio-Booster Armor Guyver

is a long-running manga series written by Yoshiki Takaya. The Guyver itself is a symbiotic techno-organic (or biomechanical) device that enhances the capabilities of its host.
The manga was originally serialized in Tokuma Shoten's Shonen Captain magazine beginning in 1985. When Shonen Captain was discontinued in 1997, the manga was picked up by Kadokawa Shoten who subsequently re-released all of the previous graphic novels originally published by Tokuma. The manga is currently serialized in Kadokawa's monthly Shonen Ace magazine. It has been licensed by Viz Media, Star Comics and Chuang Yi Publishing.